Charged particle beam apparatuses have many functions in a plurality of industrial fields, including, but not limited to, inspection of semiconductor devices during manufacturing, exposure systems for lithography, detecting devices and testing systems. Thus, there is a high demand for structuring and inspecting specimens within the micrometer and nanometer scale.
In particular, semiconductor technologies have created a high demand for structuring and probing specimens within the nanometer scale. Micrometer and nanometer scale process control, inspection or structuring, is often done with electron beams. Probing or structuring is often performed with electron beams which are generated and focused in electron beam devices. Examples of electron beam devices are electron microscopes, in particular scanning electron microscopes (SEM), or electron beam pattern generators. Electron beams offer superior spatial resolution compared to photon beams, due to their short wavelengths at comparable particle energy.
For semiconductor manufacturing, throughput can be a significant limitation in tools for scanning a geometry in its entirety. Assuming a SEM resolution of 1 nm, a 10 mm2 die contains 10E14 pixels. Accordingly, for covering the entire layout, a fast inspection architecture is desired. For achieving high throughput at a desired signal to noise ratio (SNR), it is desired to have an electron beam device with a high electron beam intensity.
However, at high electron beam intensity the interaction between electrons of the electron beam have an increasing effect on the beam. Due to the electron-electron interactions, the energy and spatial resolution of the beam is decreased. Therefore, measures to mitigate the electron-electron interactions of the beam have been devised, such as a broadening of the primary electron beam. However, there is still a need to reduce the effect of electron-electron interactions even further.